Question
Which of the following scientist does not have any contribution in cell theory?
- Robert Brown
- Rudolph Virchow
- Schleiden
- Schwann
Hint:
The cell theory was proposed by two scientists- Schleiden (1838)and Schwann (1839).
The correct answer is: Robert Brown
- The cell theory was proposed by two scientists- Schleiden (1838) and Schwann (1839). It says that all the plants and animals are composed of cells and the cell is the basic unit of life. The cell theory was further expanded by Virchow (1855).
- Robert Brown observed a near-circular spot which was slightly more opaque than the other places. He again observed the same structure in other cells as well. Brown coined the term areola to describe them at first. Although this spot was observed previously by other scientists, Robert understood the significance of this structure and finally named it nucleus.
- So Robert Brown has no contribution in the cell theory
Related Questions to study
This picture is of ________.
This picture is of ________.
The organism which contain only one cell is called as__________.
The organism which contain only one cell is called as__________.
Cell was discovered in the year_______.
Cell was discovered in the year_______.
Cell membrane is a part of_________.
Cell membrane is a part of_________.
Sensory receptors are specialized to perceive a certain kind of
The electrical signals are also known as action potential, which is transferred to the brain for decoding.
Sensory receptors are specialized to perceive a certain kind of
The electrical signals are also known as action potential, which is transferred to the brain for decoding.
The exchange of gases takes place in
The alveoli have more concentration of carbon dioxide as compared to oxygen to creat a concentration gradient.
The exchange of gases takes place in
The alveoli have more concentration of carbon dioxide as compared to oxygen to creat a concentration gradient.
Which gas is exhaled out from the body?
The process of respiration involves two acts occurring simultaneously, that is, removal of carbon dioxide and inhaling of oxygen.
Which gas is exhaled out from the body?
The process of respiration involves two acts occurring simultaneously, that is, removal of carbon dioxide and inhaling of oxygen.
Which organ is used to break down food mechanically?
Mechanical breakdown is crucial for the enzymes to act on it. Larger the surface area, the easier it is for enzymes to breakdown the substances.
Which organ is used to break down food mechanically?
Mechanical breakdown is crucial for the enzymes to act on it. Larger the surface area, the easier it is for enzymes to breakdown the substances.
Which of the following is the accessory organ of the digestive system?
The small intestine is the main area for digestion and absorption.
Which of the following is the accessory organ of the digestive system?
The small intestine is the main area for digestion and absorption.
Which of the following is a sac-like structure in the excretory system?
There are certain sensors present on the surface of the urinary bladder which sends a signal to the brain in case, the bladder becomes full.
Which of the following is a sac-like structure in the excretory system?
There are certain sensors present on the surface of the urinary bladder which sends a signal to the brain in case, the bladder becomes full.
Lungs are involved in
Respiration is a crucial process required for keeping the organism alive.
Lungs are involved in
Respiration is a crucial process required for keeping the organism alive.
The human heart consists of
The valves are present in the heart which prevent the backflow of the blood.
The human heart consists of
The valves are present in the heart which prevent the backflow of the blood.
HCl in the stomach helps in
The HCl is also released when we don't consume food for a long time. This causes acidity.
HCl in the stomach helps in
The HCl is also released when we don't consume food for a long time. This causes acidity.
Which of the following is an example of a unicellular organism?
Amoeba reproduces by asexual reproduction such as fission.
Which of the following is an example of a unicellular organism?
Amoeba reproduces by asexual reproduction such as fission.
Which two organs are involved in the nervous system?
The neurons convert the different forms of energy from the stimulus into electrical energy.
Which two organs are involved in the nervous system?
The neurons convert the different forms of energy from the stimulus into electrical energy.
